SILVER SPRING, Md. — Discovery Communications Inc., the owner of pay-TV channels such as Discovery, TLC and Animal Planet, said Tuesday that its third-quarter net income declined 14 percent due in part to higher taxes and interest expenses. Its revenue held steady.

The company also lowered its full-year outlook and shares fell in morning trading.

The company earned $205 million, or 55 cents per share, in the July-September period, down from $237 million, or 59 cents per share, a year earlier. Earnings from ongoing businesses totaled $214 million, or 57 cents per share, in the latest quarter.

Revenue was flat at $1.08 billion.

Analysts, on average, were expecting earnings of 63 cents per share on revenue of $1.09 billion, according to a poll by FactSet.

The company said that foreign currency fluctuations, stock-based compensation expenses, higher taxes and interest expenses contributed to the decline in its net income.

For 2012, Discovery expects revenue of about $4.48 billion to $4.53 billion. In July, it had forecast revenue of $4.55 billion to $4.65 billion for the year. Analysts are expecting higher revenue of $4.56 billion.

The company also lowered its earnings outlook to between $975 million and about $1.03 billion from between $1 billion to $1.1 billion.

Discovery’s shares fell $2.18, or 3.7 percent, to $57.27 in late morning trading. The stock peaked for the year at $62.36 in mid-October. It traded as low as $38.86 last November.